The Healthy People 2020 evidence-based resources identified have been selected by subject matter experts at the U.S. Department of Health and Human Services. Each of the selected evidence-based resources has been rated and classified according to a set of specific criteria based, in part, on publication status, publication type, and number of studies. This classification scheme does no necessarily consider all dimensions of quality, such as statistical significance, effect size (e.g., magnitude of effect), meaningfulness of effect, additional effect over control, and study design (e.g., sample size, power, internal validity, external validity, generalizability, potential biases, potential confounders).

What do the ratings mean?All of the resources in this tool are based on intervention evaluations or studies that have evidence of effectiveness, feasibility, reach, sustainability, and transferability. The ratings indicate how strong the evidence is.

4 out of 4These resources are based on rigorous evidence. Resources with this rating include systematic reviews of published intervention evaluations or studies that have evidence of effectiveness, feasibility, reach, sustainability, and transferability.

Examples:

Recommendations of the Community Preventive Services Task Force

Recommendations of the U.S. Preventive Services Task Force

Systematic reviews published in peer-reviewed journals

3 out of 4These resources are based on strong evidence. Resources with this rating include non-systematic reviews of published intervention evaluations or studies that have evidence of effectiveness, feasibility, reach, sustainability, and transferability.

Examples:

Non-systematic reviews published by the Federal Government

Non-systematic reviews published in peer-reviewed journals

2 out of 4These resources are based on moderate evidence. Resources with this rating include intervention evaluations or studies with peer review that have evidence of effectiveness, feasibility, reach, sustainability, and transferability.

Examples:

Journal articles of individual studies

Published intervention research

Published pilot studies

1 out of 4These resources are based on weak evidence. Resources with this rating include intervention evaluations or studies without peer review that have evidence of effectiveness, feasibility, reach, sustainability, and transferability.

Examples:

Unpublished intervention research

Unpublished pilot studies

Unpublished case studies

Unpublished field-based summaries

What are the differences between the ratings?4 vs. 3: A rating of 4 requires a formal, comprehensive, and systematic review of all relevant literature whereas a rating of 3 only requires an informal, non-comprehensive, non-systematic review of some but not all relevant literature.

3 vs. 2: A rating of 3 requires a review of multiple evaluations or studies whereas a rating of 2 only requires one evaluation or study.

2 vs. 1: A rating of 2 requires peer review whereas a rating of 1 does not require peer review.

What criteria were used to identify these resources?Each of the selected evidence-based resources has been rated and classified according to the criteria in the rating system. These criteria include:

Is it a formal, comprehensive, systematic review?

Was it peer reviewed and published?

Does it include multiple evaluations or studies?

The rating system does not measure all dimensions of quality. Some other measures that are not included in the rating system are:

Can you define the types of resources displayed?Systematic Review: A systematic review is a critical assessment and evaluation of all research studies that address a particular issue. Researchers use an organized method of locating, assembling, and evaluating a body of literature on a particular topic using a set of specific criteria. A systematic review typically includes a description of the findings of the collection of research studies. The systematic review may or may not include a quantitative pooling of data, called a meta-analysis.

Nonsystematic Review: A non-systematic review is a critical assessment and evaluation of some but not all research studies that address a particular issue. Researchers do not use an organized method of locating, assembling, and evaluating a body of literature on a particular topic, possibly using a set of specific criteria. A non-systematic review typically includes a description of the findings of the collection of research studies. The non-systematic review may or may not include a quantitative pooling of data, called a meta-analysis.

Randomized Control Trial: A randomized control trial is a controlled clinical trial that randomly (by chance) assigns participants to two or more groups. There are various methods to randomize study participants to their groups.

Cohort Study: A cohort study is a clinical research study in which people who presently have a certain condition or receive a particular treatment are followed over time and compared with another group of people who are not affected by the condition.

Cross-Sectional or Prevalence Study: A cross-sectional or prevalence study is a study that examines how often or how frequently a disease or condition occurs in a group of people. Prevalence is calculated by dividing the number of people who have the disease or condition by the total number of people in the group.

Case-Control Study: A case-control study identifies all incident cases that develop the outcome of interest and compares their exposure history with the exposure history of controls sampled at random from everyone within the cohort who is still at risk for developing the outcome of interest.

Expert Opinion: The opinion of someone widely recognized as a reliable source of knowledge, technique, or skill whose faculty for judging or deciding rightly, justly, or wisely is accorded authority and status by their peers or the public in a specific well-distinguished domain.

Pilot Study: A pilot study is a small-scale experiment or set of observations undertaken to decide how and whether to launch a full-scale project.

Experimental Study: An experimental study is a type of evaluation that seeks to determine whether a program or intervention had the intended causal effect on program participants.

Practice-based example: A practice-based example is an original investigation undertaken in order to gain new knowledge partly by means of practice and the outcomes of that practice.

Peer-Reviewed: A publication that contains original articles that have been written by scientists and evaluated for technical and scientific quality and correctness by other experts in the same field.

What are the Leading Health Indicators (LHIs)?Healthy People 2020 provides a comprehensive set of 10-year national goals and objectives for improving the health of all Americans. Healthy People 2020 is composed of more than 1,200 objectives across 42 Topic Areas.

A smaller set of Healthy People 2020 objectives, called Leading Health Indicators, has been selected to communicate high-priority health issues and actions that can be taken to address them.

What are some search tips for using the evidence-based resources tool?

The shading of the check boxes will show you what criteria can be searched. You might want to begin with a broad search first. You can always narrow your results further using the Search Criteria sidebar on the left-hand side of the page.

Be sure to reset the search form before starting a new search. A link is provided at the top of the search results.

When filling out your search, be sure to scroll through all the choices before clicking on the Search button.

A quick way to change your search is to stay on the results page and use the Search Criteria sidebar. Your search results will be filtered accordingly.

Why can’t I search the database for some Topic Areas and other categories of information?Topic Areas are dimmed in the dropdown menus to indicate that there are no resources available in the database at the time of your search. The same is true for specific search criteria, such as age ranges. We are continually adding evidence-based resources to the database. As resources become available, you will have the opportunity to choose from more Topic Areas, objectives, and search criteria.

Who developed this evidence-based resource tool?The U.S. Department of Health and Human Services’ Office of Disease Prevention and Health Promotion developed this tool with guidance, input, and support from:

The Healthy People 2020 Federal Interagency Workgroup (FIW)

The FIW’s Implementation Strategies Subgroup

The Healthy People 2020 Workgroup Coordinators

The National Institutes of Health’s Office of Disease Prevention

Who identified these evidence-based resources?Subject matter experts at the U.S. Department of Health and Human Services who comprise the Healthy People 2020 Workgroup Coordinators for the relevant Healthy People 2020 Topic Area. The list of Healthy People Topic Areas can be found here. The list of Healthy People Workgroup Coordinators can be found here.

Who developed the rating system?The rating system was:

Developed by the Centers for Disease Control and Prevention’s Best Practices Workgroup

Revised by the Healthy People 2020 Implementation Strategies Subgroup

Approved by the Healthy People 2020 Federal Interagency Workgroup

The ratings were developed to identify evidence-based resources and interventions that may be used to achieve targets set forth in Healthy People 2020. The Healthy People 2020 evidence-based resource tool is managed by the Office of Disease Prevention and Health Promotion at the U.S. Department of Health and Human Services and supported, in part, by funds from the National Institutes of Health’s Office of Disease Prevention.